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SECTION V--DESCRIPTION OF STRATEGIES Objective 11.1 A--Reduce the Number of Motorcycle Crashes by Incorporating Motorcycle-Friendly Roadway Design, Traffic Control, Construction, and Maintenance Policies and Practices Strategy 11.1 A1--Provide Full Paved Shoulders to Accommodate Roadside Motorcycle Recovery and Breakdowns (T) General Description Shoulders are desirable for all vehicle types, but provide particular benefits to motorcyclists. For example, motorcyclists that run off the roadway or experience mechanical problems within a confined cross section (e.g., bridge, work zone) with no shoulder are especially vulnerable to traffic following in their path of travel. That is, motorcyclists do not have a vehicle to provide at least limited protection and to make them more visible to oncoming or following traffic. By widening the shoulders, or providing a shoulder where one previously did not exist, motorcyclists have a refuge area out of the traveled way to accommodate motorcycle breakdowns. They also have more recovery area to regain control of their errant motorcycle before encroaching on the roadside, thereby reducing the risk of an impact with a fixed roadside object. While there are no reliable studies in the literature that document the safety benefits to motorcyclists of providing full paved shoulders, the relationship between shoulder width and safety has been studied extensively for motor vehicles in the rural environment. An expert panel (Harwood, 2000) recently reviewed the literature on safety for shoulder widths on rural two-lane highways for the Interactive Highway Safety Design Model (IHSDM). The panel concluded that the most credible studies of shoulder width on rural two-lane highways were those by Zegeer et al. (1981) for low-volume roads and another study by Zegeer et al. (1988) for higher-volume roads. The expert panel developed accident modification factors (AMFs) based on these past studies. AMFs are used in accident prediction algorithms to represent the safety effects of various geometric features (e.g., shoulder width, right-turn lanes, etc.). The base value of each AMF is 1.0. Any feature associated with a higher accident experience than the base condition has an AMF with a value greater than 1.0, and any feature associated with lower accident experience than the base condition has an AMF with a value less than 1.0. Another expert panel in a later research study (Harwood et al., 2003) concluded that the AMFs for rural two-lane highways are also the best available estimates for rural multilane highways. Strategy 15.1 A8 in NCHRP Report 500, Volume 6: A Guide for Addressing Run-Off-Road Collisions also addresses shoulder treatments and may be referenced for further details, including a complete list of the technical attributes of this strategy. The Run-Off-Road (ROR) guide provides one set of accident modification factors for widening a paved shoulder on a two-lane rural highway and a second set of accident modification factors for various shoulder types and widths. To achieve the desired safety improvements, highway agencies may find it helpful to consider whether their design policies for new or reconstructed roadways--including the shoulder width and type of shoulder to be used--take into consideration motorcycle safety. V-7

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SECTION V--DESCRIPTION OF STRATEGIES A review of existing roadways, where a full paved shoulder is not provided, may be appropriate to identify locations that could be problematic for motorcyclists. Full paved shoulders may be targeted to high-crash locations. Since many highway agencies have not yet adopted an organizational motorcycle safety philosophy, highway agency personnel need to be trained to identify locations where the lack of a full paved shoulder may be problematic for motorcycles. Information on Agencies or Organizations Currently Implementing This Strategy The state of Iowa has conducted a study to evaluate the costs and benefits associated with paved shoulders on primary highways in the state. This study reviewed current design criteria as well as state crash data and decided upon a minimum 3-ft paved shoulder width on rural highways in the state. Visit http://www.ctre.iastate.edu/reports/pavedshoulder.pdf for more information. Strategy 11.1 A2--Consider Motorcycles in the Selection of Roadside Barriers (E) General Description Historically, roadside safety barriers have been installed to protect errant motor vehicles from encroaching on fixed objects located beyond the barrier. In most cases, the installation of safety barriers has only taken into consideration the needs and concerns of passenger cars, trucks, and other motor vehicles, while the needs of motorcyclists are typically overlooked. For example, with post and rail or wire rope barriers, there is the chance that the rider could slide under the rail or wire and continue off the roadside. Other traditional roadside barriers may be too low, and do not protect motorcyclists vaulted from their vehicle. When this happens, the rider is not only subjected to possible injury from the tops of posts should he or she come in contact with them, but the rider may continue off the roadside. FARS data for 2006 show that fatal crashes involving fixed objects constituted a little more than one-quarter of all fatal crashes. Bryden and Fortuniewicz (1986) conducted field investigations for 3,302 traffic barrier crashes in the state of New York in order to determine the barriers' performance as different types and sizes of vehicles collided with them. They found that crashes involving motorcycles were by far the most severe. Nearly 50 percent of crashes involving motorcycles resulted in either a fatality or severe injury, and in approximately 12 percent of those crashes, the motorcyclist ended up beyond the traffic barrier. NCHRP Report 350 (Ross et al., 1993) presents procedures for conducting vehicle crash tests and in-service evaluation of roadside safety features or appurtenances. Types of devices included are: (1) longitudinal barriers (such as bridge rails, guardrails, median barriers, transitions, and terminals); (2) crash cushions; (3) breakaway or yielding supports for signs and luminaries; (4) breakaway utility poles; (5) truck-mounted attenuators; and (6) work zone traffic control devices. FHWA requires use of NCHRP Report 350 testing protocols for all roadside safety hardware. As currently established, there are no protocols covering the performance of roadside barriers based on collisions with motorcycles. V-8

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SECTION V--DESCRIPTION OF STRATEGIES There are three main types of barrier systems currently used in the United States: Concrete barriers W-beam guide rails and three-beam rail systems Wire rope safety barriers (WRSBs) Each of these provides unique benefits and detriments to motorcyclists based on their physical properties and placement along the roadside. Concrete barriers, such as the one illustrated in Exhibit V-2, are the most rigid barriers in use and are often found in locations where there is limited space for barrier deflection, and/or where traffic volumes are significant and the relative frequency of impacts is higher. These barrier systems are made of interlocking sections that form a continuous smooth surface that is most advantageous in collisions where impact angle is small because it prevents snagging and blunt force impacts (from posts) to the motorcyclist. Research by Sala and Astori (1998) determined that the physical nature of concrete barriers enabled sliding and redirection of the crash victim in addition to providing a significant distribution of contact forces over the surface area of the barrier. Highway agencies may want to consider installation of concrete barriers at high-crash locations or at locations with the greatest potential for motorcycle/ barrier collisions. Appropriate locations for their application include sites with high motorcycle traffic volumes, high motorcycle accident rates, and locations where current roadside barriers are deemed problematic for motorcyclists. The W-beam guide rail, as the name suggests, consists of a "W" shaped rail supported by posts incrementally spaced to provide sufficient strength to withstand collisions. Exhibit V-3 illustrates a W-beam guide rail. Because these barriers are not as rigid as their concrete counterparts, they do provide a significant amount of deflection during impacts with heavier vehicles. The most undesirable features of this design, from the motorcyclist's perspective, are the posts and the sharp edges associated with them, which are exposed both above and below the guide rail. Should a motorcyclist be ejected from the vehicle across the top of the guide rail, he or she could be severely injured by the tops of the posts. More common, however, is the possibility of a motorcyclist passing under the protective rail and then coming in contact with the lower portion of a post. In these situations, even EXHIBIT V-3 EXHIBIT V-2 W-beam Guide Rail Concrete Roadside Barrier (New Jersey Type) V-9

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-4 if the angle of impact is relatively small, the impact Wire Rope Safety Barrier with the post surface will be approximately perpendicular. Studies by Ouellet (1982) and Domhan (1987) have each shown that collisions with guide rail posts are often severe, if not fatal. Even if a person could travel between guide rail posts without coming in contact with them, there is often a roadside hazard (from which the guide rail is protecting the roadway user) directly beyond the guide rail. Similar in many aspects to W-beam guide rails, WRSBs (Exhibit V-4) are generally composed of three or four lateral wire rope segments that are supported by vertical posts and tensioned by anchors at incremental spaces. These barriers are used in environments where there is ample space for deflection and they provide very little impediment to sight distance. The motorcycle safety issues associated with WRSBs are twofold. First, the supporting posts for this barrier pose the same threat to motorcyclists as the posts for the W-beam guide rails discussed above. Secondly, the greatest perceived concern for motorcyclists unique to this design is the potential to be severed by the wire rope. This type of barrier device is much less expensive to implement than concrete or W-beam guardrail. Its widespread application on open medians of freeways has gained substantial interest in recent years and met with great success in eliminating cross- median head-on crashes involving motor vehicles. Given the relative newness of this design treatment there is a general lack of research on its performance when impacted by motorcyclists. It is understood in the design community that the best solutions to roadside hazards are eliminating the hazard itself. Thus, preference is to remove trees, objects, etc. and flatten slopes versus placing barriers to shield vehicles from them. However, quite clearly there are many, frequent situations where roadside barriers are necessary to provide overall system safety. Given that historically the basis for roadside appurtenance design uses larger vehicles and does not directly consider motorcycle impacts, the safety effectiveness of motorcycle- friendly roadside barriers is largely unknown. Further research to quantify the safety benefits of these systems is needed. EXHIBIT V-5 Strategy Attributes for Considering Motorcycles in the Selection of Roadside Barriers Technical Attributes Target The strategy is targeted to reduce the severity of collisions resulting from motorcyclists coming in contact with a roadside barrier. The strategy is also targeted at agencies responsible for the placement of such treatments. Expected Effectiveness This strategy should reduce motorcyclists' exposure to serious injury due to collisions with roadside barriers. V-10

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-5 (Continued) Strategy Attributes for Considering Motorcycles in the Selection of Roadside Barriers There is no consensus on a quantitative estimate of the safety effectiveness of this strategy. The effectiveness likely depends on the number of locations where non-conforming barrier treatments were replaced, the volume and speed of motorcycle traffic at the location, and motorcycle accident patterns at the location. Keys to Success The key to the success of this strategy will be the existence of a policy and a set of procedures that requires the identification of high-risk locations due to poorly engineered barriers and the replacement or modification of these barriers. Potential Difficulties The cost of replacing or constructing roadside barriers could be significant compared to other road treatments. This may limit the number of locations in which this strategy could be introduced. Some barriers that are not conducive to motorcycle safety may still be sufficient to protect other motor vehicles; thus, replacing otherwise acceptable barriers may be difficult. Keeping sufficient maintenance on motorcycle-safe barriers after collisions have occurred may be difficult. Appropriate Measures Key process measures include the number of locations where insufficient or and Data dangerous roadside barriers have been replaced with motorcycle-friendly barriers, and the severity of accidents reduced by the improvement. Crash frequency and severity, by type of crash, are key safety effectiveness measures. It is especially useful to identify crashes related to collision with a roadside barrier and analyze them separately. Crash frequency and severity data are needed to evaluate such improvements. If feasible, both total crashes and crashes related to barrier collisions should be analyzed separately. Motorcycle traffic volume data are needed to represent exposure. Associated Needs There are no particular public information and education needs to be addressed when this strategy is implemented. Communication regarding the presence of these roadway improvements to the motorcycle riding community would be beneficial but not essential. Organizational and Institutional Attributes Organizational, Highway and other agencies should make sure that their design policies for new Institutional and or reconstructed roadways incorporate a consideration of how potential roadside Policy Issues barriers will affect the motorcycle population. Highway agencies should review their barrier warrant policies and maintenance practices regarding the use of concrete, W-beam and WRSB barriers to ensure that appropriate action is being taken on routine projects. Nearly any highway agency can participate in implementing this strategy, which is applicable to rural, urban, and suburban areas. This strategy is complemented by effective stakeholder partnerships. Coordinating with a state/region motorcycle advisory group will serve to inform the motorcycle community of this effort, and will provide a conduit for information to the agency of potential problem areas. Issues Affecting This strategy can be implemented within 3 months of identifying a location with Implementation Time unacceptable roadside barriers. V-11

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-5 (Continued) Strategy Attributes for Considering Motorcycles in the Selection of Roadside Barriers Costs Involved The costs involved in this strategy are all related to the identification of harmful locations and the engineering and installation of new roadside barriers. Training and Other Highway agency personnel should be trained to identify high priority locations and Personnel Needs install new treatments in a manner that will effectively improve the roadway environment. Highway agency personnel should also be made aware of the multitude of roadside barrier options that are available. Legislative Needs None identified. Other Key Attributes Compatibility of This strategy can be used in conjunction with most others for improving Different Strategies safety for motorcyclists. Other Key Attributes to None identified. a Particular Strategy Strategy 11.1 A3--Identify Pavement Markings, Surface Materials, and Other Treatments That Reduce Traction for Motorcycles and Treat or Replace with High-Traction Material (T) General Description Painted roadway markings and other surface materials can be extremely slippery when wet. In fact, slick materials that interfere with traction are applied to road surfaces with increasing frequency. The National Agenda for Motorcycle Safety (NHTSA, 2000) made the following proposal: Take steps to remove slippery sealants and repair substances applied to road surfaces. A motorcycle's traction can be seriously compromised by a variety of surface treatments, including: Bituminous rubberized asphalt sealer (used for crack repair) Plasticized adhesive pavement-marking tape Manhole covers Raised pavement markers While each of these treatments is particularly slick in wet conditions, some may even be slippery in dry environments. These treatments become even more problematic for motorcyclists when they are installed in horizontal curves where a leaning motorcycle can potentially slip and crash. Where bituminous rubberized asphalt sealers are applied to large areas, more motorcyclists can be adversely affected. Often this material is applied in widths of 12 to 24 in. As the material warms, it becomes gummy and may cause a motorcycle to slip on contact. Bridge joints that are treated with generously applied asphalt sealer can also be problematic for motorcycles. V-12

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SECTION V--DESCRIPTION OF STRATEGIES In some conditions (i.e., wet pavement and hot temperatures), this material becomes very slippery and can cause a motorcycle traveling in a straight line to lose control and fall. Plasticized adhesive pavement markings and large painted lines present traction problems. Usually located at an intersection, motorcyclists pass over these markings while leaning. Depending on speed and lean angle, these markings can cause a motorcyclist to lose traction and fall. Manhole covers become extremely slippery when wet. Compounding this problem is the fact that manhole covers often blend with the roadway color and are difficult to see at night or in low-light conditions. Treating the cover with a non-slip material and edging it in contrasting color would provide greater traction and make the cover more visible. While raised pavement markers (a.k.a. "traffic buttons") do not create a slick surface in the same way that asphalt sealers and plasticized adhesives do, they serve as potential obstacles in the roadway that can cause a motorcyclist to lose control, especially when the motorcycle operator fails to notice them. Since there is no known design standard for traction coefficient for surface treatments and manhole covers, it is difficult to define specifically when these treatments pose a problem for motorcycles. Research is needed to create a uniform standard under which agencies can make these determinations. Also, a number of highway agencies routinely test marking materials such as paints, thermoplastics, epoxies, and temporary tapes to evaluate their retroreflectivity and durability. Routine testing of marking materials should consider including a test for the traction needed by motorcycles and reflect the compatibility of these applied materials to motorcycles in various temperatures and wet and dry conditions. For example, plasticized adhesive pavement markings may be available in a "grit" surface that provides better traction when a motorcycle crosses in a lean and/or in wet or reduced traction conditions. Highway agencies may want to first target high-crash locations and routes with high motorcycle volumes. EXHIBIT V-6 Strategy Attributes for Identifying Pavement Markings, Surface Materials, and Other Treatments That Reduce Traction for Motorcycles and Treating or Replacing with High-Traction Material Technical Attributes Target The strategy is targeted to reduce the frequency of collisions resulting from motor- cyclists losing control while traversing pavement markings, surface treatments, manhole covers, or raised pavement markers that present an obstacle or provide inadequate surface friction. The strategy is also targeted at agencies responsible for the placement of such treatments. Expected Effectiveness This strategy should reduce crashes involving motorcycle loss of control due to raised pavement markers or reduced traction surface treatments. There is no consensus on a quantitative estimate of the safety effectiveness of this strategy. The effectiveness likely depends on the number of locations where raised pavement markers and reduced traction surface treatments were replaced, the volume and speed of motorcycle traffic at the location, and the available sight distance to the surface treatment or reduced traction location. V-13

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-6 (Continued) Strategy Attributes for Identifying Pavement Markings, Surface Materials, and Other Treatments That Reduce Traction for Motorcycles and Treating or Replacing with High-Traction Material Keys to Success The key to the success of this strategy will be the existence of a policy and a set of procedures that requires the identification of raised and low-traction roadway markings and the replacement or modification of these markings and road surface materials. Potential Difficulties The cost of high-traction materials may be higher than conventional road treatments. This may limit the number of locations in which this material could be introduced. Budget constraints may also limit the use of these high-traction materials. High-traction materials may be more difficult to maintain. Appropriate Measures Key process measures include the number of locations where raised or slick and Data pavement markings or surface treatments have been replaced with low-profile, high-traction material and treatments, and the number of accidents eliminated by the improvement. Crash frequency and severity, by type of crash, are key safety effectiveness measures. It is especially useful to identify crashes related to reduced traction and analyze them separately. Crash frequency and severity data are needed to evaluate such improvements. If feasible, both total crashes and crashes related to reduced traction should be analyzed separately. Motorcycle traffic volume data are needed to represent exposure. Associated Needs There are no particular public information and education needs to be addressed when this strategy is implemented. Communication regarding the presence of these roadway improvements to the motorcycle riding community would be beneficial but not essential. Organizational and Institutional Attributes Organizational, Highway and other agencies should make sure that their design policies for new or Institutional and reconstructed roadways incorporate provision of low-profile, high-traction pavement Policy Issues marking materials and surface treatments. Highway agencies should review their pavement marking policies and maintenance practices regarding use of low-profile, high-traction pavement marking materials and surface treatments to ensure that appropriate action is being taken on routine projects. Nearly any highway agency can participate in implementing this strategy, which is applicable to rural, urban, and suburban areas. This strategy is complemented by effective stakeholder partnerships. Coordinating with a state/region motorcycle advisory group will serve to inform the motorcycle community of this effort, and will provide a conduit for information to the agency of potential problem areas. Issues Affecting This strategy can be implemented within 3 months of identifying a location with raised Implementation Time markers and/or reduced traction. Costs Involved The cost of high-traction markings may be higher than conventional markings. Training and Other Highway agency personnel should be trained to apply materials in a manner to Personnel Needs preserve traction for motorcycles and to identify locations with reduced traction. Highway agency personnel should also be made aware of the different traction materials or pavement markings that are available. Legislative Needs None identified. V-14

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-6 (Continued) Strategy Attributes for Identifying Pavement Markings, Surface Materials, and Other Treatments That Reduce Traction for Motorcycles and Treating or Replacing with High-Traction Material Other Key Attributes Compatibility of This strategy can be used in conjunction with most others for improving Different Strategies safety for motorcyclists. Other Key Attributes None identified. to a Particular Strategy Information on Agencies or Organizations Currently Implementing This Strategy The Oregon Department of Transportation contacts the TEAM OREGON Motorcycle Safety Program when a new surface treatment is applied or tested. A member of the TEAM OREGON program visits the site(s), test rides the material or application, and takes photographs. A brief report is provided from TEAM OREGON to ODOT on the suitability of the product or application to motorcycle use. The Idaho Department of Transportation has purchased a grooving system. It is more labor intensive, but it appears to improve roadway traction. The Montana Department of Transportation uses a 40-mm wide reservoir and underfills it, thus minimizing the spread of asphalt sealer on the road surface. Economics was the driving force behind this effort. Strategy 11.1 A4--Maintain the Roadway to Minimize Surface Irregularities and Discontinuities (T) General Description General "wear-and-tear" on the roadway system--caused by adverse weather conditions, increasing traffic volumes, and heavy vehicle loads--is inevitable. However, it can deteriorate the roadway surface to such a condition that motorcyclists traverse the roadway with great difficulty. While it is not feasible for every surface irregularity to be treated immediately, it is essential that those irregularities and discontinuities that present an inherent problem to motorcycle users be identified and treated as quickly as possible. Highway agencies may want to first target high-crash locations and routes with high motorcycle volumes. In fact, the National Agenda for Motorcycle Safety (NHTSA, 2000) has listed "maintaining roadway surfaces" as an essential proposal. Common surface irregularities that are especially problematic for motorcycle users include potholes, tire rutting, surface drop-offs or rises, manhole covers, deteriorating pavement and railroad grade crossings that are worn or cross the roadway at a shallow angle. Each is discussed below: Potholes--While potholes are often an inconvenience for motor vehicles, due to the jarring involved as a tire suddenly dips into an opening in the road, they are even V-15

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-7 Example of a Pothole That Would Be Problematic for Motorcyclists more of a problem for single-track vehicles whose balance is more easily disrupted by the sudden jarring action. Motorcycle tires range in size from 10 to 18 inches in diameter, so even small holes in the road can cause a motorcyclist to lose control (see Exhibit V-7). Tire Ruts--It is not uncommon, especially on freeways, for tire ruts to be present on the roadway surface due to heavy truck traffic; however, a motorcyclist can have a particularly difficult time maneuvering in and out of the ruts without over-steering or over-correcting in the process. When a rut is filled with water from a rainstorm, the condition is amplified by the hydroplaning affect, leaving the motorcyclist to find a narrow path along the EXHIBIT V-8 center or edge of the lane. Pavement Drop-off Due to Repaving Project Surface Drop-offs--Another type of surface irregular- ity, surface drop-off or rise, can be found at either end of bridges or resurfacing project locations (see Exhibit V-8). If the elevation change is too drastic, the surface irregularity can be problematic for motorcyclists. Manhole Covers--Manhole covers are especially problematic for motorcyclists when they are not placed flush with the pavement surface. That is, manhole covers that are either too high (creating a raised object in the roadway) or too low (creating a "crater" or "pothole" effect) can cause a motorcyclist to lose control. This mis- alignment creates a problem when the cover suddenly appears from beneath the vehicle ahead. Manhole covers that are too high are often found V-16

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SECTION V--DESCRIPTION OF STRATEGIES in construction zones where they are first installed, or relocated, and then the final surface courses are added. Compounding this problem is the fact that manhole covers often blend with the roadway color and are difficult to see at night or in low-light conditions. Exhibit V-9 illustrates a manhole cover that is too low and blends in with the roadway color. Edging the cover in contrasting color would make the cover more visible. Deteriorating Pavement--Pavements that are poorly maintained can deteriorate and break apart, leaving a patch of broken pavement and gravel through which motor- cyclists must negotiate (see Exhibit V-10). Such debris can deflect a motorcycle's wheel when it is struck, causing the rider to lose control of the motorcycle. There are certain locations where debris is a particular problem for motorcycles, such as at horizontal curves (where insufficient traction can result in running off the road or motorcycle slide-out) or locations with limited maneuvering space (such that a rider is unable to negotiate around the debris). Railroad Grade Crossings--Outdated and well-worn railroad crossings are a rugged surface that, if not carefully traversed by motorcyclists, can easily lead to a loss of balance and control. Also, railroad crossings that do not cross the roadway at right angles can be especially difficult for motorcyclists to navigate, especially with worn crossings. The jarring impact of striking the track coupled with the slick surface can result in a loss of control. Currently there is no surface irregularity/discontinuity threshold for motorcycles. Therefore, officials have no way to quantify to what degree various surface irregularities affect motorcyclists. Further research should be conducted to develop thresholds that can be incorporated into design criteria. Highway agencies should regularly and systematically inspect all roadway surfaces for irregularities and discontinuities that potentially pose a safety problem for motorcyclists. Patchwork may serve as a temporary solution until permanent repairs can be made. However, care should be taken that the repair work is of good quality. EXHIBIT V-10 Deteriorating Pavement and Gravel from Poor Roadway Maintenance EXHIBIT V-9 Manhole Cover V-17

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SECTION V--DESCRIPTION OF STRATEGIES Strategy 11.1 A6--Reduce Roadway Debris--Such As Gravel, Shorn Treads, Snow and Ice Control Treatments (Sand/Salt), and That Resulting From Uncovered Loads--From the Roadway and Roadside (T) General Description Roadway debris poses a greater problem for motorcycles than for larger vehicles. Debris can deflect a motorcycle's wheel when it is struck, causing the rider to lose control of the motorcycle. Debris such as sand, cinders, gravel and substances spilled from trucks (grain, sawdust, fuel oils, etc.) can cause a motorcyclist to lose traction and control. There are certain locations where debris is a particular problem for motorcycles, such as at horizontal curves (where insufficient traction can result in running off the road or motorcycle slide-out) or locations with limited maneuvering space (such that a rider is unable to negotiate around the debris). Exhibit V-17 illustrates a horizontal curve with roadway debris. Common types of debris that pose a particular problem to motorcyclists include: Dirt, gravel, cinders or wood chips resulting from uncovered truck loads (Exhibit V-18) Dirt, gravel or mud introduced by cars entering a paved roadway from an unpaved roadway (Exhibit V-19) Sand or cinders remaining from winter snow and ice treatment Shorn tire treads (Exhibit V-20) Miscellaneous debris that cannot easily be traversed (i.e., mufflers, cardboard boxes, garbage, and mattresses) Roadway debris affecting motorcycle traffic can be divided into two categories: that which is safely traversable and that which is not. For debris that can be safely traversed, such as dirt or gravel, the rider must be cautious to avoid actions requiring increased levels of traction (e.g., turning, lane changing, and braking). Larger objects, such as tire treads, rocks, displaced utility covers and other large roadway debris can appear EXHIBIT V-17 Roadway Debris on Curve from beneath the vehicle ahead, right in the path of the following motorcycle. These conditions present a very precarious condition for motorcycles. A self-reported survey of Australian motorcyclists conducted by de Rome et al. (2002) found that 67 percent of those involved in single-vehicle crashes and 56 percent of those involved in multiple- vehicle crashes pointed to loss of traction as a factor. Similarly, Haworth (1999) reported that surface traction played a part in 53 percent of all motorcycle crashes and directly contributed to V-24

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-18 Debris from Uncovered Truck Load 15 percent of motorcycle crashes. For all non-traversable debris, the key concerns for motorcyclists include (1) having sufficient sight distance to recognize the obstacle and perform necessary steering to avoid a collision and (2) having sufficient space within their traveled lane to avoid the object. Potential solutions include integration of this strategy with a street repair and maintenance hotline. An agency can be notified immediately of the presence of the debris and take immediate action to remove it from the roadway or roadside. Coordination with other departments (e.g., snow and ice control treatments, city public works, etc.) may also lead to the development of a modified road sweeping schedule that could reduce the potential for roadway debris related to the activities of other roadway maintenance departments. In areas where sand, gravel or mud is repeatedly brought onto the roadway, consideration should be EXHIBIT V-19 Dirt from Unpaved Roadway EXHIBIT V-20 Shorn Tire Treads V-25

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SECTION V--DESCRIPTION OF STRATEGIES given to paving a small portion (50 ft) of the problem section nearest the intersection. Larger debris items should be removed from the roadway surface as quickly as possible to avoid being struck by an unsuspecting motorcyclist. Highway maintenance personnel should look for debris as part of routine inspections (see Strategy 11.1 A8 below). In addition, law enforcement and other public agency personnel that travel the roads frequently should be alerted to the problem, and provided instructions on how to deal with or report it. Highway agencies may want to first target high-crash locations and routes with high motorcycle volumes. EXHIBIT V-21 Strategy Attributes for Reducing Roadway Debris--Such as Gravel, Shorn Treads, Snow and Ice Control Treatments (Sand/Salt), and That Resulting From Uncovered Loads--From the Roadway and Roadside Technical Attributes Target The target for this strategy is roadway surfaces where debris that is a potential problem for motorcyclists accumulates. Expected Effectiveness Reducing roadway debris should reduce motorcycle crashes attributed to roadway debris or poor roadway surfaces. However, no quantitative estimates of the safety effectiveness of removing roadway debris are available. Further research is needed to quantify the effectiveness of this strategy. This strategy should be supplemented with an effort to better educate motorcyclists on how to handle their vehicle when they encounter situations where debris is present. See Objective 11.1C. Keys to Success A key to the success of this strategy is developing practical debris removal programs that are implemented in a consistent and sustained manner. Once a program is established, it is important that highway agencies devote staff to the ongoing effort of identifying locations with debris and removing the debris. Roadway surfaces need to be continually monitored. Involvement of public agency personnel can also be valuable for identifying roadway debris hazards and reporting them. Effective sanctions applied to those who contribute to road debris are a key to success. There are many areas of the United States that currently assess a fine to vehicle operators found contributing debris to roadways. One form of this is the littering fine imposed on anyone found discarding materials on or along the road. Also, there are laws in place inflicting heavy fines on motor vehicle operators found transporting "uncovered" materials as illustrated above in Exhibit V-18. Provision of mechanisms to report, record, and manage information on road debris hazards will greatly facilitate further actions. Toll-free telephone numbers and websites dedicated to receiving reports are needed. Potential Difficulties The major difficulty associated with removing roadway debris is the sheer enormity of the task. Because debris is continually being deposited on the roadway surface and many highway agencies have many miles of roadway within their jurisdiction, it requires a major effort to effectively combat the problem. Another potential difficulty lies in gaining support for allocating adequate resources to regularly remove debris. V-26

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-21 (Continued) Strategy Attributes for Reducing Roadway Debris--Such as Gravel, Shorn Treads, Snow and Ice Control Treatments (Sand/Salt), and That Resulting From Uncovered Loads--From the Roadway and Roadside Appropriate Measures Key process measures include adoption or revision of policies that support and Data this strategy, new budgets established to support the effort, person-hours devoted to the effort, and the number of locations at which roadway debris is removed. Crash frequency and severity are key safety effectiveness measures. Separate analysis of the crash types targeted by the improvement is desirable. The number of motorcycles potentially affected by the debris removal may be used as a surrogate measure of effectiveness, at least until crash statistics become available. Crash frequency and severity data are needed to evaluate such improvements. If feasible, both total crashes and crashes related to roadway debris should be analyzed separately. Traffic volume data are needed to represent exposure, particularly exposure in the areas in which the roadway debris is typically located. Associated Needs The major needs associated with this strategy are mechanical equipment and manpower required to remove roadway debris. Organizational and Institutional Attributes Organizational, Highway agencies should consider the adoption of roadway debris removal as Institutional and standard maintenance practice for roadways with moderate to high motorcycle Policy Issues volumes. The involvement of other public agency personnel, who drive the roads regularly, should be sought in a cooperative venture. This would require interagency contact and cooperation. Nearly any highway agency can make use of this strategy. Issues Affecting Implementation of this strategy is an ongoing effort rather than a one-time treatment. Implementation Time Initial implementation, including policies, interagency cooperation, introductory training, establishment of reporting centers, and management information systems could require as much as 1 year to accomplish. Costs Involved Costs are highly variable, depending on the extent of the system implemented, and the amount of debris typically found on the roadways in a jurisdiction. Again, this is an ongoing effort, so the costs will be ongoing. Training and Other Limited introductory training may be needed for those being asked to report and Personnel Needs address roadway debris. Legislative Needs Laws, or revisions thereto, may be needed to establish sanctions for those who cause debris on roadways. Other Key Attributes None Identified. V-27

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SECTION V--DESCRIPTION OF STRATEGIES Strategy 11.1 A7--Provide Advance Warning Signs to Alert Motorcyclists of Reduced Traction and Irregular Roadway Surfaces (T) General Description Advance warning signs inform motorists of reduced traction and irregular roadway surfaces. Such signs require caution on the part of the driver and may call for a reduction in speed or other maneuver. Advance warning signs are typically geared to all types of vehicles and do not typically address one particular vehicle type. The exception to this is advance warning signs that specifically address large trucks (e.g., truck-tipping signs that warn trucks of a sharp horizontal curve, signs that warn trucks of a steep grade ahead, etc.). Another group of roadway users that could benefit from advance warning signs is motor- cyclists. There are a number of roadway conditions that are potentially problematic for motorcyclists. With proper advance warning, motorcyclists can take necessary steps to safely negotiate through those conditions. Advance warning signs for motorcyclists should be considered for the following situations: Where speed may have to be reduced--Roadway surface irregularities (e.g., gravel, uneven pavement, longitudinal grooves, steel grate bridge deck, and pavement ending) and reduced traction surfaces (e.g., water across roadway, moss in perpetual wet and shaded areas) may require a reduction in speed (see Exhibit V-22). Where lateral placement is limited or may have to be modified--Roadway surface irregularities (e.g., gravel, uneven pavement, longitudinal grooves and gaps) and wind gust areas may require a change in lateral placement (see Exhibit V-23). Potential conflict zones--Anywhere that surface traction or stability may be compromised (e.g., gravel, oil treatments, longitudinal differences in pavement elevation) represents a potential conflict zone. Work zones--The frequency of steel plates, gravel, sand, uneven pavement, and longitu- dinal grooves in construction and work zones make these areas particularly problematic for motorcyclists. EXHIBIT V-22 EXHIBIT V-23 Grooved Pavement Warning Sign Irregular Roadway Surface and Advance Warning Sign Sign V-28

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SECTION V--DESCRIPTION OF STRATEGIES Advance warning signs in these situations may be EXHIBIT V-24 beneficial for all drivers. However, due to the unique Advance Warning Sign for Motorcyclists characteristics of motorcycles, it is particularly important that advance warning signs be placed well in advance of the location with reduced traction or irregular roadway surface to provide motorcyclists with sufficient time to react appropriately. Highway agencies may want to first target high-crash locations and routes with high motorcycle volumes. Exhibit V-24 illustrates an example of an advance warning sign geared to motorcyclists. Further research should be conducted to determine the feasibility of developing a series of basic motorcycle warning signs that could be integrated into the MUTCD. EXHIBIT V-25 Strategy Attributes for Providing Advance Warning Signs to Alert Motorcyclists of Reduced Traction and Irregular Roadway Surfaces Technical Attributes Target The target of this strategy is locations with reduced traction or irregular roadway surfaces that cannot be otherwise mitigated. Expected Effectiveness The effectiveness of this strategy in reducing crashes has not been satisfactorily quantified. Nevertheless, there is a general consensus that advance warning signs can help reduce confusion and maximize perception/reaction time at locations with reduced traction or irregular roadway surface. Further research to develop safety effectiveness measures for this strategy is desirable. Keys to Success A key to success in applying this strategy is to identify appropriate locations that would benefit from advance warning signs. The location of the sign is important because advance warning signs that are placed either too far or not far enough in advance of a problematic roadway condition will make the signing less effective. Table 2C-4 in the MUTCD (http://mutcd.fhwa.dot.gov/kno-millennium.htm) presents guidelines for advance placement of warning signs relative to the type of roadway condition and the posted or 85th-percentile speed on the roadway. Advance warning signs should be applied with consistency and uniformity. Engineering judgment should, where possible, be accompanied by a human factor assessment of the need for advance warning signs. Cooperation between agencies will also be a key to success since one agency will be responsible for identification of the problematic roadway condition and the development of appropriate signage while another agency will be responsible for installation. Another key to success is the ability and commitment of the highway agency to adequately maintain the signs. Potential Difficulties Care should be taken not to overuse advance warning signs, and to place appropriate distance between the different signs. The objective is not to overload the driver with information so that the signs become the cause of confusion. Agencies should strive to use advance warning signs only where a special problem or circumstance indicates the need, and to maintain a certain consistency and uniformity to their application. V-29

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-25 (Continued) Strategy Attributes for Providing Advance Warning Signs to Alert Motorcyclists of Reduced Traction and Irregular Roadway Surfaces Appropriate Measures Key process measures are the number and type of advance warning signs placed, and Data or the number of locations for which advance signing is provided. Crash frequency and severity, by type, are key safety effectiveness measures. Both total crashes and crash types potentially affected by the use of advance warning signs should be analyzed separately. Geographic analysis of crash location can lead to the identification of "black spots" where countermeasures may be most useful. Driver behavior (e.g., erratic maneuvers, near misses, conflicts) may be used as surrogate safety measures. Traffic volume data are needed to represent exposure. Associated Needs None identified. Organizational and Institutional Attributes Organizational, Adoption of new highway signs should proceed through the normal MUTCD process Institutional and before being widely used. It is possible that some pilot testing can be done at Policy Issues the state or local level, but under strictly controlled conditions and using a valid evaluation design. Nearly any highway agency can participate in the implementation of this strategy. State highway agencies that implement this strategy may serve as a role model for local agencies, even to the extent of developing a "best practices" manual for local agencies to use in making decisions about providing advance warning signs. A general policy may need to be developed to provide the foundation for a long-term and consistent commitment to the strategy. This strategy is complemented by effective stakeholder partnerships. Coordinating with a motorcycle advisory group will serve to inform the motorcycle community of this effort, and will provide a conduit for information to the agency of potential problem areas. Issues Affecting This strategy does not require a long development process. Signing improvements Implementation Time can typically be implemented in 3 months or less. Policy development and adoption, if required, could extend the implementation period. Costs Involved Short-term costs for implementing this strategy include the cost of the signs themselves. Longer-term costs include the cost to maintain the signs. Training and Other Training regarding use of this strategy should be provided in highway agency Personnel Needs training courses concerning the use of traffic control devices, including the special needs of motorcyclists. Legislative Needs None identified. Other Key Attributes Compatibility of This strategy can be used in conjunction with most other strategies for improving safety. Different Strategies Other Key Attributes to None identified. a Particular Strategy V-30

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SECTION V--DESCRIPTION OF STRATEGIES Information on Agencies or Organizations Currently Implementing This Strategy The Oregon Department of Transportation posts motorcycle-specific signs warning motor- cyclists of changing roadway conditions, such as "Rain Grooves Ahead." The New Hampshire Department of Transportation also posts motorcycle-specific warnings. The Virginia Department of Transportation formed a Motorcycle Safety Action team to (1) heighten awareness of motorcyclists with resident engineers, (2) add language to the VA Work Zone Protection Manual and classroom training, (3) create signs for longitudinal joints, (4) create signs for certain transverse (expansion) joints, (5) meet with various utility providers regarding hazards for motorcyclists, (6) develop an informational flyer for distribution, and (7) evaluate an anti-skid treatment for steel plates. For information, visit their website at http://www. virginiadot.org/programs/resources/3motorcycle.pdf. Strategy 11.1 A8--Incorporate Motorcycle Safety Considerations into Routine Roadway Inspections (E) General Description Typically, highway agencies perform a routine visual site investigation of the entire roadway network within their jurisdiction. The investigator reviews the condition of such roadway elements as pavement, pavement markings, traffic signs, traffic signals, and roadside elements (including guide rail) to identify potential problems and repair needs. While the investigation may be conducted with all vehicles in mind, it is more likely that the unique characteristics and needs of motorcycles are not thoroughly considered. Previous strategies have identified a number of roadway conditions (i.e., surface irregularities and discontinuities) that may not be a problem for motor vehicles, but are problematic for motorcyclists, including: Roadway debris such as tire treads, rocks, mufflers and other large objects that can cause loss of stability and control. Roadway debris such as sand, gravel, mud and moss that can cause a loss in traction. Temporary surface treatments such as gravel roads and culvert fills, steel plates, abrupt pavement drops and rises can erode with time and become increasingly problematic for motorcycles. Such roadway surface problems should be identified by highway agency personnel through routine roadway inspections. In fact, motorcycle considerations could be incorporated into maintenance management systems. EXHIBIT V-26 Strategy Attributes for Incorporating Motorcycle Safety Considerations into Routine Roadway Inspections Technical Attributes Target The strategy is targeted at maintenance and other personnel who periodically conduct inspections of roads in their jurisdiction. Expected Effectiveness No quantitative estimates of the safety effectiveness of this strategy are available. However, identifying and fixing roadway conditions that are problematic for motorcyclists would be considered an effective step towards providing a more comfortable and safe environment for motorcyclists. V-31

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-26 (Continued) Strategy Attributes for Incorporating Motorcycle Safety Considerations into Routine Roadway Inspections Keys to Success The key to success is identifying problematic roadway conditions in a timely manner and conducting a high-quality repair. Establishing policies and procedures within the agencies will be important to success. It will also be helpful for efforts to be made to sensitize staff to hazards faced by motorcyclists. Potential Difficulties The greatest difficulty is developing the skills and perspectives necessary for the personnel responsible for roadway inspections to recognize potential conflict areas for motorcyclists. Another potential difficulty is overcoming the tendency of highway agencies to assume that the needs of all single-track vehicles (e.g., motorcycles and bicycles) are the same. The needs of motorcycle riders are very different from those of bicycle riders and should not be grouped together. Appropriate Measures Key process measures include documenting the existence of the desired policies and and Data the number of locations where adverse roadway conditions have been corrected. Crash frequency and severity, by type of crash, are key safety effectiveness measures. It is especially useful to identify crashes related to poor roadway conditions and analyze them separately. Crash frequency and severity data are needed to evaluate such improvements. If feasible, both total crashes and crashes related to poor roadway conditions should be analyzed separately. Motorcycle traffic volume data are needed to represent exposure. Associated Needs None identified. Organizational and Institutional Attributes Organizational, This strategy depends on adequate training of highway agency inspection personnel Institutional and to properly identify roadway conditions that are problematic for motorcyclists. Policy Issues This strategy also depends on allocation of funds to conduct repairs. Nearly any highway agency can participate in implementing this strategy. This strategy is complemented by effective stakeholder partnerships. Coordinating with a motorcycle advisory group can serve to inform the motorcycle community of this effort and provide a conduit through which motorcyclists can inform the agency of potential problem areas. Issues Affecting Establishing policy and procedures may take as long as 6 months to 1 year, including Implementation Time time to inform and train personnel to implement any changes. It is likely that repairs can be implemented within a few days to a few months of identifying the problem. Costs Involved The costs involved in this strategy depend largely on the extent of problems identified and corrected. Training and Other Highway agency personnel should be trained to identify roadway conditions that are Personnel Needs problematic for motorcyclists, and instructed on how to correct them. Legislative Needs None identified. Other Key Attributes None identified. V-32

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SECTION V--DESCRIPTION OF STRATEGIES Strategy 11.1 A9--Provide a Mechanism for Road Users to Notify Highway Agencies of Roadway Conditions That Present a Potential Problem to Motorcyclists (E) General Description A number of roadway conditions (i.e., surface irregularities and discontinuities) that are problematic for motorcyclists have been identified in previous strategies within this objective. Such roadway surface problems should be identified by highway agency personnel through routine roadway inspections, as discussed in Strategy 11.1 A8. However, regularly inspecting all roadway miles within their jurisdiction is a daunting task for highway agency personnel, and it is possible that a surface irregularity (e.g., pothole, gravel, etc.) may go unnoticed for several days. Motorcyclists, on the other hand, are very adept at recognizing surface irregularities that are problematic for them. Therefore, highway agencies would benefit from having a mechanism (e.g., toll-free number, website, etc.) whereby motorcyclists or other roadway users can report roadway surface problems. A toll-free number could be answered by a member of the highway agency staff or it could provide a voicemail for callers to leave a message. Of course, voicemail left at the toll-free number or email sent to a website would need to be checked regularly and in a timely manner by highway agency staff. EXHIBIT V-27 Strategy Attributes for Providing a Mechanism for Road Users to Notify Highway Agencies of Roadway Conditions That Present a Potential Problem to Motorcyclists Technical Attributes Target The strategy is targeted at road users who may want to report hazardous conditions for motorcyclists to the responsible agency. Expected Effectiveness No quantitative estimates of the safety effectiveness of this strategy are available. However, providing a smoother, more continuous roadway surface would certainly be considered an effective step towards providing a more comfortable and safe environment for motorcyclists. Keys to Success If the reporting system is to be used, road users must be made aware of it. Success will also depend upon how timely and appropriately the agency responds to reports of problematic roadway conditions. Potential Difficulties Potential difficulties include malfunctioning of the mechanism (i.e., website goes down, data are not managed properly) and poor response time to reported problems. Also, there is a potential tort liability issue with this strategy that would need to be resolved within the highway agency. That is, once an agency is put on notice of a problem, they may be considered liable; should they not address the problem in a timely manner, there is an increased risk of a successful lawsuit from someone encountering the problem. Appropriate Measures Key process measures include documentation of the establishment of a road- and Data user reporting system, the number of reports received, the number of locations checked, and the number of locations where adverse roadway conditions have been corrected. V-33

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-27 (Continued) Strategy Attributes for Providing a Mechanism for Road Users to Notify Highway Agencies of Roadway Conditions That Present a Potential Problem to Motorcyclists Crash frequency and severity, by type of crash, are key safety effectiveness measures. It is especially important to identify crashes related to poor roadway conditions and analyze them separately. Crash frequency and severity data are needed to evaluate such improvements. If feasible, both total crashes and crashes related to poor roadway conditions should be analyzed separately. Motorcycle traffic volume data are needed to represent exposure, particularly in areas where road maintenance problems have been reported. Associated Needs None identified. Organizational and Institutional Attributes Organizational, This strategy depends on the allocation of key resources (i.e., money and staff) to Institutional and receive, manage, and respond to reports of problematic roadway conditions. Policy Issues Attempts may be made to add the activity of receiving and managing reports to staff that are already very busy. If the effort is going to be effective, the reports need to be handled in an expeditious manner. Nearly any highway agency can participate in implementing this strategy. This strategy is complemented by effective stakeholder partnerships. Coordinating with a motorcycle advisory group can serve to inform the motorcycle community of this effort and provide a conduit for motorcyclists to inform the agency of potential problem areas. Issues Affecting It may take 6 months to establish the system for receiving and managing the reports. Implementation Time The timeframe required for reacting to reports, once received by maintenance personnel, will depend upon the nature of the roadway problem reported. It is likely that repairs can be implemented within a few days to a few months of identifying the problem. Costs Involved The costs involved in this strategy depend largely on the nature of the problem reported. Establishing a call-in number and a website, along with software to enter and manage the reports, should be relatively low-cost. However, some equipment may be needed to facilitate this strategy. Training and Other Highway agency personnel should be trained to work the "hotline" mechanism-- Personnel Needs to receive and quickly respond to reported problems, as well as monitor progress to ensure response and quality control. Legislative Needs None identified. Other Key Attributes None identified. V-34